ABSTRACT
Marijuana is the most widely used illicit drug of abuse in the United States. In the case of marijuana, its toxicity is relevant both for the acute and the chronic situations. In the acute situation, it has been postulated that marijuana impairs performance in various tasks. Although it is possible that the effect of marijuana on the human brain involves several mechanisms, it is important to start to delineate the consequences of the different effects on the human brain and their ultimate relation with the process of reinforcement, addiction, and toxicity. Differences in regional brain glucose metabolism for the absolute and relative values between baseline and delta-9-tetra hydro cannabinol (THC) intoxication were tested using paired t tests. The whole-brain metabolic response to the effects of THC was equally variable among individuals; some subjects showed increase, some decrease, and some did not show change. Despite these variable responses in whole-brain metabolism, there was a very consistent pattern of metabolic activation by THC.
